microsoft/playwright · error · Error

"text" engine expects a single string

Error message

"text" engine expects a single string

What it means

Error ""text" engine expects a single string" thrown in microsoft/playwright.

Source

Thrown at packages/injected/src/selectorEvaluator.ts:465

  },

  matches(element: Element, args: (string | number | Selector)[], context: QueryContext, evaluator: SelectorEvaluator): boolean {
    return evaluator.matches(element, args, { ...context, pierceShadow: false });
  }
};

const visibleEngine: SelectorEngine = {
  matches(element: Element, args: (string | number | Selector)[], context: QueryContext, evaluator: SelectorEvaluator): boolean {
    if (args.length)
      throw new Error(`"visible" engine expects no arguments`);
    return isElementVisible(element);
  }
};

const textEngine: SelectorEngine = {
  matches(element: Element, args: (string | number | Selector)[], context: QueryContext, evaluator: SelectorEvaluator): boolean {
    if (args.length !== 1 || typeof args[0] !== 'string')
      throw new Error(`"text" engine expects a single string`);
    const text = normalizeWhiteSpace(args[0]).toLowerCase();
    const matcher = (elementText: ElementText) => elementText.normalized.toLowerCase().includes(text);
    return elementMatchesText((evaluator as SelectorEvaluatorImpl)._cacheText, element, matcher) === 'self';
  },
};

const textIsEngine: SelectorEngine = {
  matches(element: Element, args: (string | number | Selector)[], context: QueryContext, evaluator: SelectorEvaluator): boolean {
    if (args.length !== 1 || typeof args[0] !== 'string')
      throw new Error(`"text-is" engine expects a single string`);
    const text = normalizeWhiteSpace(args[0]);
    const matcher = (elementText: ElementText) => {
      if (!text && !elementText.immediate.length)
        return true;
      return elementText.immediate.some(s => normalizeWhiteSpace(s) === text);
    };
    return elementMatchesText((evaluator as SelectorEvaluatorImpl)._cacheText, element, matcher) !== 'none';
  },

View on GitHub (pinned to c8fc3bf8d3)

When it happens

Trigger: Thrown at packages/injected/src/selectorEvaluator.ts:465 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of microsoft/playwright@c8fc3bf8d3 (2026-08-12). Data as JSON: /api/errors/0513e76c94d0d83e. Report an issue: GitHub.